Related Field
The present disclosure relates to a hydraulic cylinder for an aircraft landing gear.
Description of Related Art
United States Patent Application Publication No. 2011/107756 A1 describes a hydraulic cylinder for an aircraft landing gear. This hydraulic cylinder includes a cylinder tube, a piston, and a snubbing mechanism. The piston defines oil chambers in the cylinder tube, and reciprocates by supplying and discharging hydraulic oil into and from the oil chambers. After the piston approaches the end of its stroke, the snubbing mechanism reduces the moving speed of the piston to reduce shock generated when the piston reaches the end of its stroke.
The snubbing mechanism includes a supply/discharge port which opens through the inner circumferential surface of the cylinder tube in the vicinity of the end of the stroke of the piston and through which hydraulic oil is supplied and discharged into and from the cylinder tube, and a snubber ring connected to the piston and having a circumferential surface that slides over the inner circumferential surface of the cylinder tube and has slits. When the piston approaches the end of the stroke, the piston covers the supply/discharge port, and the associated oil chamber communicates with the supply/discharge port through the slits of the snubber ring. In this state, the slits function as throttle oil passages, and the flow rate of hydraulic oil discharged from the oil chamber decreases. As a result, the moving speed of the piston decreases.